Electrolytic process of salvaging uranium



Dec. il, 1956 R. Q. BOYER TL ELECTROLYTIC PROCESS OF SALVAGING URANIUM Filed Sept. 14, 1944 5 Sheets-Sheet 1 56077' B. /f/l. NER

ATTORNEY.

Dec. 11, 1956 R. Q. BOYER ETAL 2,773,820

ELECTROLYTIC PROCESS oF SALVAGING URANIUM Filed Sept. 14, 1944 5 Sheets-Sheet 2' 0 39 3&2 36 3/ ad .as

ATTORNEY.

Dec, 11, 1956 R. Q. BOYER ETAL ELECTROLYTIC PROCESS OF SALVAGING URANIUM 5 Sheets-Sheet 3 Filed Sept. 14, 1944 1 INVENTOR. Raaf/Pr C2 orf/P .56077 M W- ATTORNEY.

Dec. 11, 1956 R, Q. BOYER ETAL ELECTROLYTIC ,PROCESS OF' SALVAGING URANIUM Filed sept. 14,4 1944 5 Sheets-Sheet 4 mm\\| AI www w INVENTOR. Raaf/w Q. Boff/P 5c rf 5. /f/L NER ATTORNEY.

Dec. l1, 1956 R. Q. BOYER ETAL ELECTROLYTIC PROCESS OF SALVAGING URANIUM Filed Sept. 14, 1944 5 Sheets-Sheet 5 Mar-v ATTORNEY. Y

Unite i ares Robert Q. Boyer and Scott B. Kilner, Berkeley, Calif., assignors to the United States of America as represented by the United States Atomic Energy Commission Application September 14, 1944, Serial No. 554,044

7 Claims. (Cl. 204124) The present invention relates to improved electrolytc processes that are especially adapted for use in conjunction with the salvage of uranium from wash solutions derived from calutrons employed in the calutron method of producing uranium enriched with U235.

In the copending application of Ernest O. Lawrence, Serial No. 557,784, filed October 9, 1944, which issued as U. S. Patent No. 2,709,222 on May 24, 1955, there is disclosed a calutron, a machine designed to separate the constituent isotopes of an element and, more particularly, to increase the proportion of a selected isotope in an element containing several isotopes, in order to produce the element enriched with the selected isotope. More speciiically, the calutron mentioned is especially designed to produce uranium enriched with the isotope U235- ln the copending application of James M. Carter and Martin D. Kamen, Serial No. 532,159, led April 21, 1944, which issued as Patent No. 2,758,006 on 'August 7, 1956.

' arent there is disclosed an improved process of producing uracalutron or a second-stage calutron the compound UCls is treated, whereby a residue of the UCL; is deposited on the parts of the calutron disposed in the source region thereof, metallic uranium enriched with U235 is deposited in the first pocket of the collector of the calutron, and metallic uranium impoverished with respect to U235 is deposited in the second pocket of the collector of the calutron. The deposit of UCL; is recovered by a water wash step and the deposits of metallic uranium arevs'epa-x rately recovered by acid wash steps; and the three wa'sh solutions are separately purified, if required, to produce three separate batches of a given compound of uranium. In this process, a first batch of the uranium compound mentioned, produced from the water wash derived from a first-stage calutron, is then converted back to UCl4 for retreatment in the first-stage calutron, and a second batch l of the uranium compound mentioned, produced from the water wash derived from a second-stage calutron, is then converted back to UCL; for re-treatment in the secondstage calutron.

ln the copending application of Martin D. Kamen and Abel De Haan, Serial No. 542,378, filed June 27, 1944,

there is disclosed an improved process of purifying av water wash solution of the character mentioned in order to separate uranium from metallic impurities in the solution. In accordance with this process, a water wash solution containing uranium, copper, nickel, iron and chromium in thefonn of chlorides is rst concentrated; and

the `:concentratedA 'solution containing UO2++, Cuit,V

ff* Y 2,773,820 Patented Dec. 11, 1956 2 Ni++, Fe+++ and Cr+++ ions is then reduced electrolytically, whereby the uranyl ion, UO2++,`and the ferrie ion, Fe+++, are respectively reduced to the uranous ion, U++++, and the ferrous ion, Fe++. Thus, the reduced solution contains U++++, Cu++, Ni++, Fe++ and Cr+++ ions; and to this reduced solution there is added oxalic acid, whereby the uranium is precipitated as U(C2O4)z-6H-2O away from the metal impurities in the solution. The solution is then filtered in order to Sepaf rate the uranous oxalate precipitate, leaving the metal ions mentioned in the filtrate; and the given compound of uranium is converted back to UCl4 for further treatment in the appropriate one of the calutrons, as previously explained.

In accordance with this process, the filtrate obtained after separating the -uranous oxalate contains traces of uranium and fairly large amounts of nickel, iron, copper and chromium; this solution containing U++++, Ni++, Fe++, Cu++ and Cr+++ ions is then subjected to a calcium oxalate carrier salvage treatment in order to recover the traces of uranium. This salvage treatment is very irnportant in conjunction with the filtrate obtained from the wash water solution derived from-the second-stage calutron, in view of the fact that the last-mentioned filtrate constitutes an oxalate solution of relatively large volume and the uranium contained therein has been singly enriched with U235 due to the previous treatment thereof in the first-stage calutron. Thus, it is essential that none of the valuable, singly-enriched uranium contained in this oxalate solution be lost to the outside.

While the salvage of the uranium from the oxalate solution mentioned, by the calcium oxalate carrier treatment, is entirely satisfactory in operation, it is essentially a laboratory process not particularly well adapted to large scale commercial use.

Accordingly, it is an object of the invention to provide an improved process of salvaging the uranium from a solution of the character mentioned thatmay be readily carried out on a commercial scale and in an economical manner.

A further object of the invention is to provide an improved process of salvaging traces of uranium contained in a relatively large volume of solution by treatment in an electrolytic cell. y

A further object of the invention is to provide an improved process of rtreating in an electrolytic cell a vsolution derived from a calutron wash solution, whereby` A further object of the invention is to provide an imi proved process of decomposing electrolytically a compound that is decomposable by chlorine oxidation in solution.

A-further object of the invention is to provide an improved process of decomposing electrolytically an oxalate f solution".

A further object of the invention is to provide an improved process of concentrating electrolytically uranium in solution.

' The invention, bothy as toits organization and method of operation togther with further objects and advantages thereof, will best be understood by reference to thegfol-A lowing specification taken in connection with the accompan'ying drawings, in which Figure 1 is a fragmentary plan View of an electrolytic cell with which there may be carried out the process Vof the present invention; Fig. 2

"upper surface of the bottom wall 17, the individual paris a ,fragmentary longitudinal sectional view of -thetelec trolytic cell taken along the line 2 2 in Fig. l; Fig. 3 is a transverse sectional view of the electrolytic cell taken along the line 3%3 in Fig. 2; Fig. 4 is a transverse sec-- tionalview of the electrolyftic cell taken -along thetlline` 4-,4 in Fig. 2;.Fig. 5 is a transverse sectional viewcf the electrolyticcell taken along therlinefS-#S in Fig. 2; Fig. 6 is an enlarged fragmentary sectional view oione of-the anode compartments in theelectrolytic cell', taken along the lined-.6 in FigfS; Fig.v 7 is an enlarged fragmentary sectionalview of Athe lower'portion of the left` hand, sidezwall of the upper casinglsectionof the' electro-- lytic cell,;takc11 alongthe. line 7-.7 'in Fig. .6,tandnillus-- tratingthe arrangementof Ithe.. .gas..conduit.embedded therein; Fig. k8 isa reduced sidefelevational view,:.-partlyA in ilsection,y of the housinggof,the.=elect1olytic.v cellpand Fig. 9 is a diagrammatic illustration of a solution1-treatj` ment systemin which theelectrolytic celll is incorporated.

Referring now.more'fparticularlynto (Figsgzrl .to in.-.`

clusive,-ofthedrawings, there is illustrated anrelectroly-tic cell 10,that:compr i ses a lowereasing se'c`ton:,111and..anc`

upper., asingvsectionllZ. The lower casing.,section. 11 is.

substantially, rectangulan in plan, including .a at ,bottomV wa1lf13,upstandingnside Y,walls. 14 fand upstanding; end, walls, 1S, seured, together in, liquid-tight, relation,;.the,; Perimeter. of; the. f bottQm wall ,13.being...receivedA .inv in-4 terior A grooyes` V'forrnecl in,then'side-;.walls.f14, andA in. the endwalls 15` adjacentthe lower edges,l;here of., .Further,

the ;10Wrasiae Section llgirlcltldes a rectanaularaout-` Wardlrxtsndiasilange .1.6 disposed. aboutthe-uppsrropeni endthereof and rigidly secured .to -the-,adyacentoutenf surfaceslgoflthe l., `side walls v14 andh the r end walls." 15.51. Similarly, the upper casingrsectionm12- is subtsantially rectangularin plan, including a at l otto mwall 17, up l standing'side-walls ,218, anddupstanding end walls 19, se-

cured together in liquid`tight relation, the lowerfedges i of the -s idegwalls18 andthe `end walls 19 being received in a rectangular groove formed in the. .upper surface of thel` bottom wall17, and. disposedrinwardly from theA perimeterthereof. Accordingly, thel bottom wall 17 of theupper casingfse'ctionllZ extends outwardly from the. side'fwallsl and Athe end walls 19 in order to define-,in elect a`r'`c'tangular outwardly extending ange 20,;lisposed faboutthe .lower closed `end jof, theupper casing. section 12."- Preferably, the. parts of the. lower casing sectioiillandthe upper casing .section.1i2 arevformed 3f laminated Bakelite,Textolite or othersimilar'in-I ulating.. materiel?. Y

Tl1`:f11ppefrl casing section .12 is assembled. upon the .owerf casin'gfsection '11, the 'rectangular angesZtland l6 `being,congruent Also, a ysealing gasket21,forrned )f rbbe'nor theflil'e, fisarranged lbetween the. lower ,surl i'ace' oftliebottom .wall "17.,andtlleupper` edge of the kside ng nuts23l Washers '24 and 25 surround. the Shanks `of,

he bolts 2.2 .andare respectively"disposed'betweenthe Iea'dsjof thefbolts 22fand 'the upper surface -of` the,U lange' 20, and betweenthe nuts 23 and the, lo`wer,.s'urfa(:e

' 0 'and.16.. ,"Fi'nally, thean'ges'dfand-,.ZO. yf secured .together in .f liquidftighnrelation of ',bolts- 22`,` extendingv througlif. align'edi rrnedA vtherein,k the endslof, the bolts 22, receiv'v i if the al'nge 16. "Further, a drain pipe 26 is thiieaclecL-` ticats 'with' 'the interior of the lower'cs'ing sectiorill,

Fhe `end of thedrain. pipe 26 terminates. in. a petcoclc'l vhe're'by IlOS'd.;

A number` of laterally extending and longitudinally nl@ garant pipe 26 may be selectively' ppeneag 'or' paced-apart slotsi1v7 are provided througdthe bottom valljl'fwithin the areabounded by tlieside md' the ends` lwalls v'1 9; fand a corresponding. lpstanding laterallyv extending` andlongitudin pac part-,paired partities elements, ,2 8` are carriedyyt,

A'respeoltiye i. lnusbars...132.- l'a'node @elementsss ar .a @ninetiessaatfsletssataatawhlat tition elements 28 of each pair being disposed on the"lv opposite sides of a slot 17a. More particularly, each upstanding partition element 28 is retained in place by a pair of aligned upstanding slots 18a, formed in the inner surfaces of the side walls 18, and an aligned laterally extending recess 17b, formed in the upper surface of the bottom wall 17 adjacent a slot 17a. Thus, each partition element 28 is retained'in place in upstanding position by a substantially U-shaped composite groove comprising n a pair of upstanding slots 18a formed in the inner surfaces of the, side walls 18. and a cooperating laterally exa tending recess 171: formed in the upper surface of the bottom..wall,-17. Finally, an upstanding laterally-extending partition element 29 is carried by the upper surface of the bottom wallk 17,`the partition element 29 being spaced longitudinally and to the right-hand side of the partition element 28 disposed most remote from the lefthand end wall 19t y A1so,-the upstanding partition element 29 is retained in place by a pair of upstanding cooperating I. slots formed inthe inner surfaces of the side walls 18 and analigned laterally extending recess formed in the upper surface of the bottom wall 417, in a manner iden-v tical 'to that previously explained in conjunctionv with eachl partition element 28. v

More: panticu-larly, #the two-partition elements 28y of each pair cooperate with each other and with fthe -pontions of Y the vside walls 18 disposed therebetween Ito define a cath-A ode compartment 31 having a-n open lower end formed' Similarly, each let-hand by a cooperating. slot 17a; pantition-element-28fof a pair cooperates with lthen righthand pantitionelement- 28 `of an adjacent 4'pair and with l theipontions of the iside vWalls 18 and the 'bottom Wall 17 disposed .therebetween to define an anode compartment A 30 havingua closed flower end. Further, -theleft-hand partitiony element 28of the pair disposed 'adjacent rthe i* left-handsend wall 1K9'cooperates therewith and with the v portions of the side walls 18 andthe bottom wall 17 disposed Atherebetween 'to ldefine the anode compartment-V 304dispos'edimmediately a'dja'cenftV the left-hand endwall Y 19...-Finally,rfthefrightehand partition element 28 ofwthe pair. .disposed adjacent the'partition element 29 cooper-fw atesherewirth and with the portions of the Iside-walls 18 and-rthelbontom wall 17 disposed Itherebetween'ito f detnewtheV anode'oompa-r-tment 30 disposed m'ost remote' -'from.thedetehandendwall 19. v

'Ilh'e .upperedgeswofwthe.variousvpatirs of partition elernentsg'281g-and-ithe ipantitionlrelement 2 94 are -dis'posedI sub# stantia'llyushwith lthe upper edges of the `sidewalls 18,1,- and theiupper edges of the side walls 18 are substantially finish-with,the'.upper edges:ofthe end walls 19;'whereby theifupperredge: ofwthe .upper casing section 12 'is subif stantiallyilait'an'd parallelto the bot-tom' wall 13 of the lower casing section 11: Further, ak pair of conductors' 1 in 4tlheionmaof bus rbarsj32formed of copper or,thelike=, .varezfsecured taihenpperedges' of the sidewalls'llS by i a. nmnber ofrlscrewsgr: 'Thenleft-hand'end'sgof the=bus r bar-sg3`2J-fare:secuecl..togetl1er.by :1t-conducting fst-rapltgby screws 35; and a conducting terminal 36 is secured-'to ,thef-Hy of anodegelements l38 is carried by the Ibusba'rs 32 and"y arranged inthe respective anode compantments 30'. Each i of thev anodeelement-s 38 comprisels a substantially rectangulaiplate providedat its '.upper end with ,laltera1ly andbppositely'extending lugs `3d8a',.whielr,overhang th and hydrochloric acid solutions, sii `:l'1`fas` Igraphite fior'A platinum or a platinum-indium alloy, andare electrically connected to the b usbars 33 by terminal structure in' cluding screws 39 and'exible conductors v40.

or pigtail ftype, one end of eachpigtail 40being brazed or soldered tothe Iadjacent busbar 32, and the'otherend of :the pigtail 40 being provided with `an eyeletthrough which the `associated screw 39 extends, the Vscrew 39 extending through the .adjacent lug 38aV formed on the cooperating `anode element 38. Thus, 4the terminal 36 is connected Iby low lresistance paths Ito each of the anode Y being disposed remote from the lett-hand end Wall` andspaced some distance from fthe right-hand end wall 15. The bearing lbrackets 42 and 43 may suitably cornprise completementary sections formed of stainless steel and secured together and to the ybottom wall 17 by theV screws 44 and`45, as previously noted. The shaft41` carries a plurality of longitudinally spaced apart cathode members 46 in the form of disks. -Each of the cathode members 46 is rigidly secured .to the shat "41, so that it'- is rotatable therewith, .and extends downwardly into the lower casingV section 11 .and upwardly througha cooperating one of 'the 'slots 17a into a cooperating one of the cathode compartments 31 formed in the partition structure within the upper casing section 12. The cathode members 46 are formed yof a conducting material resistant to chlorine and hydrochloric acidsolutions .that readily amalgamates with mercury, such for example, as nickel. r)The cathode members 46 are electrically connected ito the shaft 41 in multiple Iand'collectively constitute a cathode.

A laterally extending yopening 17C is provided through,

the bottom wall 17 adjacent rthe right-hand end'wall 19; and a bevel gear 47 -is rigidly secured to the right-hand end of 'the'shaft 41, whereby the upper portion of Ithe bevel gear 47 extends `upwardly through the opening 17e into the upper casing section 12, and the lower portion of the bevel gear 47 fexitend-s downwardly into the lower casing isection 11. More particularly, the bevel gear 47 isV provided with a collar 48 which is ysecured to `the righthand end of the shaft 41 by a setscrew 49 and carries a angeSt) engaging the right-hand side of thejbearing bracket 43 to provide a thrust bearing for the shaft 41.

The bevel gear 47 meshes with a bevel gear Sl'rigidly secured to an opstanding operating shaft 52 adjacent [the lower end thereof. The extreme llower end of the operating shaft 52 is Isupported in a thrust bearing 53 carried by a bearing bracket 54; and the upper end of fthe operating 'shan'tl 52 is supported -by 'a guide bearing 5'5 carried by Ia Ibearing strap 56. More particularly, the bearing lbracket 54 comprises two laterally upwardly and outwardly' extending legs 57, which'iare secured by screws 58 -to the lower surface of the bottom wall 17, and a longitudinally upwardly .and outwardly extending leg 59, whichV is secured by the iscrew 45 Ito the lbearing bracket 43. 'Dhe thrust bearing 53 comprises a threaded step 60 accommodating adjustment of the operating sha-ft 52 vin the vertical direction, andconsequently proper xii-esh between the bevel gear 51 carried thereby and the bevel gear 47 carried by theshaft 41. The lbearing strapv 56 extends laterally across the upper casing section 11, andthe opposite ends thereof are `suitably anchored to i L .the upper edges of the sidewalls 18 by screws v61.v Y

i A pool of mercury 62 is arranged in the lower casing More particularly, the flexible conductors'40 are of the -braid section 11, the "volmo'of "the" inercuryfconstituting'the poolbein'g' such'tht'columns'of Yirl'eiclrynisein thef'sl 17a into thecathode compartments 31.pf Preferably,l columns of mercury -ris`e` 'into -"the"cathod "compertinents@ 31a slight distance 'abo'vethe upper surface oftheY botto Wall -17 'whereby the Ishaift '41 and the `lower segmentsN ffthe Icathode members46 are Vimmersed in thefinercryil` pool' '62.:v An pstding cathode plate 63 extends throughi ftheuppenfcasing section -12v downwardly `through'th opening 17c 'and-terminates in' the-'lower casing sectin 11, whereby the -lowerend of the cathode plate '63 is' Iimmersed v-in thefmercury lpool v62. .A substantially; U-shaped clip i6424 is rigidly secured to the cathodeplate and is 'adapted Ito' overhang lthe"adjacent upper' `edgeff of the right-handfend wallv 19,'thereby-securely to retain*1 the cathode plate V63- in position.V Y

Further, a body `of electrolyteV 6-5' is arranged in the; .upperl casing section 12as a headiupon ythe mercury 'poolfI 62, the body of electrolyte` 65, filling the various anode;

rfand'cathode compartments 30`and 31, respectively, and

electrically lcommunicating:through Ythe'porous f partition l' structure including the partition elements -28 land 29,"the mass Iof the body of Velectrolyte 65 beingsuch thatnth'e'* upperf'seg-ments' of the cathode members 46 are com-4 pletely'immersed therein. The .anode compartmentsl 30 inthe upper casingisectionVV 12 :are arranged-.in groups, each group continingiseveral v:adjacent individual anodev compartments', the individual anode` compartments'j in `each/group `'bein'gconnected in series relation, landtthe different groups 'ofl anode' compartments being connectedin 'parallel relation -by a iirstfconduit system. Similarly, I

12 are arranged-in groups, each group containing 'several'A adjacent individual cathode compartments, 'the individual* cathode compartments ineach group ibeing connected in series relatiomand the diierent groups of cathode compartments Ibeing connected in parallel relation by a second conduit system.

Considering now 'the electrolytic cell 10 rin greater detail, the partition structure compri-ses nine pair-s of partition elements 28, whereby nine individual cathode compartments 31 are formed in the upper casing section" 12 )and arranged in longitudinallyspaced apart relation, each of the cathode compartments 31 communicating through the associated slot 17a with the lower casing sec`V Ition 11. Also, the rotatably mounted shaft 41 carries nine Ilongitudinally spaced apart cathode members 46'v which extend through the respective slot-s 17a into the respective cathode compartments 31. Further, the partition structure comprising the Ynine pairs of partition elements 28 and the partition element 29 forms ten individual 4 Ianode compartments 30 in the upper casing section 12, arranged in longitudinally-spaced .apart relation and in interposed relation with respect to the cathode compai't ments 31. Thus, in the partition structure an-anode compartment -30 is positioned on either side ofi-each cathode' compartment 31. The ten anode compartments 30 are `arranged in three' sgi-oups, two end'groups of three individual anode compartments each andV :a middle group of four individual yanode compartments. The three groups l' of anode compartments 30 are connected in parallel, and the individual anode compartments@ in each group'are connected in lseries relation by the yfirst .conduit system mentioned. Similarly, the nine cathode compartmentsA 31 are arranged in three `groups of three` individual cathode compartments each. The three 'groups 'of cathode compartments 31 are connected in parallel and the vindividual cathode compartments 31 in 'each group Iare connected in series relation by the'second conduit'syst'em mentioned. v

Referring now more particularly lto Figs 1, 2 land'9, Y the first conduit system mentioned comprises' three inlet"- pipes 101,'respecti`ve1'y serving the three "groups ofanode compartments 30 -and respectively communicating with? the irst, fourth and eighthffindividua-l Vanode' compart` ments '30 positioned from the right-handjside of the electrolytic cell 10 toward the Ileft-hand side thereof,v as viewedin the gures mentioned. Also, the rst conduit system mentioned comprises threeoutlet pipes 102, respectively serving the three groups of anode compart-` ments `30 and respectively communicating with the third, seventh and vtenth individual anode compartments 30. The adjacent ends of the individual anode compartments in each group are connected in series relation between the associated inlet pipe 101 and the assoeiatedfoutlet pipe 10-2 by U-shaped header pipes 103. In conjunction with the rlirst conduit system, it is noted that a series of aligned openings 18b areformed in vthegside walls 18 and communicate withr the anode compartments 30 in order to receive the various pipes 101, 102 and 103, thel openings 1'8b being disposed well above the lower ends of the anodeelements 38 so that the lower portions of the anode elements are completelyimmersed in the body of electrolyte 65. d d j Accordingly, it will be understood that a first stream of electrolyte may be conducted from a lirst of the inlet pipes 101 through a rlirst 4group of three individua-l anode compartments 30 in series relation to a rst of the outlet pipes 102. Similarly, a second stream of electrolyte may be conducted from a second of the inlet pipes 101 through the second group of fou-r individual anode compartments 30 'in series relation to a second of ythe outlet pipes 102. Finally, a third stream of electrolyte may be conducted from a third of the inlet pipes 101 through the third group of three individual anode compartments 30 in series relation to a third of the outlet pipes 102. Accordin'gly, the lrst conduit system oonnects'the individual anode compartments 30 in ythe electrolytic cell I10 in parallel series relation.

The second conduit system mentioned comprises three inlet pipes 104 respectively serving the three groups of cathode compartments 31`and respectively communicating with the rst, fourth and seventh individual cathode compartments 31 positioned from theYright-hand side of the electrolytic cell 10 toward the left-hand side thereof, as viewed in the figures mentioned. Also, the second conduit system mentioned comprises three outlet pipes 105 respectively serving the three groups of cathode compartments 31 and respectively communicating with the third, sixth and ninth individual cathode compartments 31. The adjacentends of the individual cathode compartment in each group are connected in series relation between the associated inlet pipe 104 and the associated outlet pipe 105 by U-shaped header pipe 106. In conjunction With the second conduit system, it is noted that a series of yaligned openings 18C are formed in the side walls 18 and communicate with the cathode compartments 31 in order to receive theyarious pipes 104, 105 and 106, the openings 18e being disposed above the cathode members 46 so that the upper segments of the cathode members are completely immersed inl the body of electrolyte 65. d

Accordingly, it will be understood that a tirst stream of electrolyte may be conducted from a first of the inlet pipes 104 through arst group of three individual cathode compartments 31 in series relation to a first of the outet pipes 10S. Similarly, a second stream of electrolyte may b e conducted from a second of the inlet pipes 104 through the second group of threeindividnal cathode` compartments 31 in series relation to a second of the outlet pipes 105.. Finally, a third stream of electrolyte may be conducted from a third of the inlet pipes 104 through the third group of three individual Acathode compartments k31 in series relation to a third of the outlet pipes 105. Accordingly, the second conduit system connects the individual cathode compartments 3iv in the electrolytic cell 10 in parallel series relation.

`Again referring to Figs. l to 7, inclusive, it is noted that two longitudinally `extendingpipes 110fand.111 are respectivelyembedded in the'tvf/ o sidewalls '18 of the aoI upper casing section 12, the pipes and 111 being t respectively embedded in the left-hand and right-hand side walls 18, as viewed in Figs. 5 and 6. More particularly, the pipe 110 is arranged in a longitudinally extending opening formed in the left-hand side wall 18 ad jacent the lower edge thereof and cemented in place in a uid-tight manner by a layer of a suitable cement 112; and the pipe 111 is arranged in a longitudinallyextending opening formed in the right-hand sidewall 18 adjacent the lower edge thereof and cemented in place in a.

fluid-tight manner by a layer of a suitable cement 113. .i

The cement employed in the layers 112 and 113 mayl be of any suitable type, such, for example, as Bakelite A series of longitudinally spaced apart openings 11011` are formed in the pipe 110 and communicate through connecting and registering downwardly extending holesv 114 provided in the layer of cement 112iand in the left.

hand side wall 18, the holes 114 communicating with the various anode compartments 30. each hole 114 formed in the left-hand side wall 18 communicates with the associated anode compartment 30 adjacent the lower left-hand corner thereof and on the front side of the `anode element 38 arranged in the anode compartment 30, as viewed in Fig. 6. Similarly, a series of longitudinally spaced apart openings 11111 are formed 'in the pipe 111 and communicate through connecting and registering downwardly extending holes 115 provided in the layer of cement 113 and in the right-hand side wallk 18, the holes 115 communicating with the various anode compartments 30. formed in the right-hand side wall 13 communicates with the associated anode compartment 30 adjacent thelower right-hand corner thereof and 0n the back side of the anode element 3S arranged in the anode compart- Y ment 30, as viewed in Fig. 6. Accordingly, the pipe :110y

communicatesvtbrough the openings 110a with the lower left-hand corners of the various anode compartments 30 on the front sides of the anode elements 38; while the pipe 111 communicates through the openings 111ak with the lower right-hand corners of the various anode compartments 30 on the back sides of the anode elements 38.

The pipes 110 and 111 form a part of a third conduit system containing gas under pressure, whereby the gas may be forced through the pipes 110 and 111 and theA respectively communicating holes 114 and 115 into the various anode compartments 30 on either side of the anode elements 38. Also, inlet and outlet conduits 116 and 117 are supported in openings formed in the end walls 15 of the lower casing section 11 and form a part of a fourth conduit system, whereby mercury maybe circulated through the mercury pool 62 contained in the lower casing section 11.

Referring now to Fig. 8, the electrolytic cell 10 is arranged in a substantially fluid-tight housing 120 comd .prising lower and upper housing sections 121 and 122,

respectively, provided with outwardly directed flanges 123 and 124 secured ltogether by a series' of bolts 125 extending through aligned openings formed therein, a suitable sealing gasket 126, formed of rubber or the lik-e, being arranged between the flanges 123 and 124. The wall of the lower housing section 121 supports two insulating v bushings 127 and 128, arranged in gas-tight relation therewith, through which conductors are adapted to extend, whereby the positive and negative terminals of aV suitable source of supply may be-respectively connected to the terminal 36 and the plate 63, shown in Figs. vl and 2, in an appropriate manner. Also, the wall of the lower housing section 121 supports two conduits 129 and 130, arranged in gastight relation therewith, which are t appropriately connected to the pipes 101 and 102 and form a part of the iirst conduit system previously mentioned, whereby an electrolyte may be circulated through the anode compartments 30 in parallel series relation irl the manner previously explained. Similarly, the wallY of f the lower housing vsection 121 supports two conduits 131 More particularly,

More particularly, each hole 115 kand 132,- arranged in gastight 'relation therewith, whichrr are appropriately connected! to the "pipes 104-and'105 and form a part ofthesecond conduit system previouslyv mentioned, whereby an electrolyte maybe circulated through the cathode compartments 31fin parallel series relation in the -manner previously explained;

Further, the wall of i the -lower` housingsection'f'f-IZI supports a conduit 133, arranged in gastightrel'atiotif therewith, which-is appropriately connectedto fth'e' pipes 1105and 111 and forms a part of thethird 'conduit/sys#` tem previously mentioned, whereby,y gas underpressure may be conducted into the anode compartments 30VK infthe manner previously-explained.` TheV walloff'theupper housing section 122 supports a conduit 134,? arranged in gastight relation therewith,-and communicating with the interiorof the housing 120, whereby gas liberated fromv theelectrolytic cell-10 and accumulated within the 'hous-n ing 120 maybe conducted to the exterior'ina manner more-fullyexplained hereinafter. Finally, the wallof the lower housing section 121 supports two'conduits 135 and i136, arranged in'fgastight relation therewith, which'V are appropriately connectedto the pipes 116 and'117 andfform apart'of the fourthconduit system previously mentioned, whereby mercury may be circulated through the pool of^mercury162 arranged Vin the'lower casing section 11 of the electrolytic cell 10 in the manner previously explained. f

The operating shaft 52 extending into theelectrolyticl cell 10 is suitablyconnected to an electric motor 137 supported by a bracket 138i'carriedby the wall ofthe lower housing section v121; andthe wall ofthe 'lower housing section 121 supports an insulating bushing 139, arranged in gastight relation therewith, through which conductors are adapted to extend inorder 'to supply the electric motor 137 with? an operating'current.

Considering now the general operation ofthe electrolytic cell 10, when -the operating circuit for the -electric motor V137 is' completed,` operation thereof isv ini tiated, whereby the operating shaft 52 is rotated, 'causing the bevel' gear 51 Yto drive the bevel gear 47 in order to rotate the shaft v41. As the shaft`41 is rotated the cath'-` ode members`46 are `rotated, whereby"repeatedly the lower segment of each of the cathode members o r disks 46 is removed from the mercury tool 62 and immersed in the body of electrolyte 65 in the associated one of the" cathodecompartments 31, and the upper segmentther'eof is removed from theV body of electrolyte "65 in' the'asso'- ciated one'of 'thecathode compartments 31 and'immersed in the mercury pool 62. The 'electric motor 13.7"is op?"5 erated at a suitable speedin view of the gear'reduction ratio between the bevel gears 51 and 47 Vso that the'shaft 41 and consequently the disk 46 rotate at the required speed, as` explained more fully hereinafter..` Also, the operating circuit for the electrolytic'cell 10 is completed,

the anode terminal 36 and the cathode plate63'bein'g v respectively connected to the .positiveand negative' ter# minals ofthe source of direct curernt supply, whereby the body of Velectrolyte 65 oating on the pool of fuer?" cury 62Yis electrolyzed. More particularly, a rs't solu -vtion to be treated in theelectrolytic cell `1l) is conducted through theanode compartments 30via the rst conduit system mentioned;A and a second solution tobe treated A in the'electrolytic cell 10 is conducted through the cathode compartments 31 via the second conduit system mentioned; the two solutions forming an `electrolyefsystem comprising the body Vof electrolyte 65, asexplained more fully hereinafter. Also, gas underpressure is conducted intothe anode compartments 30` via the thirdl conduit systemfmentioned for a purposemore-"fully explained 70 hereinafter. Finally, mercury is conducted through the' lowercasing section 11 via thefourth vconduitsystem mentioned. The'mercury'formsa part of the lpool of mercury"62, for a purpose more ully explained here? considering new'the cansa-'aerienne arrerii the component elements "'of the ik'ele'ctrolytic :cell: greater dtaL'it-is noie'd thatinwthenspeciiic embodime of the electrolytic cell 'illustraftefdf eachrr ofthe" ha's'a diameter'approximtely l2 cm., andfappro tel 40% and 60% of its"area1are respectively the body of velectrolyte 65 andlinth'e mercury,"pool`62.

Thus,'about 80 cmof the'are'a ofeachmof the'dis-lts 46:" is 'immersed' in the 4body r'of' electrolyte 65, wherebythe f; 'Y totaly area of Ythe cathodev immersed'in thesbody; of'ell Empldvilisiw' obtained lwhen several" volts, e.V g., about jfnour, 20 current wasv appliedbetween'the anode terminal 3,6; andfj the cathode l plate 63". Under they operatingconditionsfl mentioned, it was found that three streams of theeirstl solution treated, -ofl relatively large A' volume, conducte through the three groups of anode' compartments' -`and three-streams of the'second solution treated, of rela-f tively 'smallvolume',`conducted through the threegrolvtps,"

OcathOdecOmpartments 31V, permitted operationwithl-l out undue 'jheating 'of either the 'electrolytic cell 101er the two'solutions.v More particularly, each Vof the' 30 streams of the rst solution comprised a tlow ofapproxi Y mately50 cc. per minute, while each of the three streamsv of thesecond solution comprised a `liow of approxitnatelyf',`v 5 cc. per minute,` the'temperature rise of thetwosoIu-f fionsbeing ofthe eraer'ef 55"` C. specifically.150m.;`

of the first solution'per minute and l5 cc.'of`"thelsecondf74A solutionperV minute 'were conducted through the relec f trolytic` cellAl 10,*experiencin'g a 4temperature 'rise' 15-20' C. to 70f-75 C: When` the two solutionsrvjveref conducted through the"`electrolytic1cell 10 at the rate vand underthe voperating conditions mentionedfthere was no"undue'heatilngof the component 'parts'ofthef It will be vunderstood that Vthesepax'` electrolytic cell.

ticular ow rates, as well as the atios betweenv them, are" given merely for thepurpo'seofbetter illustrating the invention, and that wide variations Vmay be made lthereinY without sacrificing any of the advantages Hof, the inyenff tion.` In' general, Vit is preferred to 'maintain such 'rc'.lai4

tive rates of ow ofthe respective electrolyte solutions ing undue heating'offthe cell# It-is' also preferred to maintain the ow conditions such vthatthe respective A aswill 'give satisfactory transferof'uranium from the,L4 viirst solution to the second, Without at the same time caus`' electrolytes 'invthe lanode and: cathode "compartmen "1' Tare atv'substantially the same-level, in* orderfto'previe mechanical transfer of electrolyte through thepartition N owconsidering the operation of the electrolytie ceY f 10, 1n conjunction with the detailed treatment of the t'wo solutions in accordance with the present process, referenceL f is again madetoFig. 9. The anode and 'cathode com manner previously explained.

. partments 30 and 31 are'initiallyjlled with a body of y" electrolyte comprising about 3 N hydrochloric acidiy then: f operation of the electrolytic cellv 1,0 is initiated inv the'f"y More particularly, the' ilow of the lirst solution to nbetreated through the anode' l compartments 30 via the iirst conduit system ,mentioned isy adjusted to aproximately 1 ,50 cc. per minute, this trstfV solution constituting the'ltraterobtained after separating the uranous oxalate precipitate following the precipitation step in the process disclosed in the Vpreviously mentioned,

application of Kamen'and De Haan. More specifically, Y the'iirst solution is anoxalic acid solution, about vl Nto 3 N hydrogen ion,"and' normally contains 'traces Tof 1 uranium and fairly large amounts ,ofy nickel," iron, copperl and Chromium, as previously'noted. Ordinarily, therst l solution; or oxalate solution, contains the materials hen 1 1 tioned in the ionic forms U++++, Ni++, Fe++, Cu++ and Cr+++, although some of the uranium and the iron might possibly be in the ionic forms UO2++ and Fe+++; and the general case will be considered, wherein the first solution is assumed to contain the following ions: UO2++, U++++, Niit, Fe+++, Fe++, Cu++ and Cr+++.

The ow of the second solution to be treated through the cathode compartments 31 via the second conduit systemmentioned is adjusted to approximately 15 cc. per minute, this second solution constituting ordinary hydrochloricwacid, about 12 N. Also, the ow of the gas through the anode compartments 30 via the third conduit system mentioned is suitably adjusted, whereby the gas is bubbled and thoroughly dispersed through the electrolyte contained in the anode compartments 30, this gas being introduced adjacent the lower corners of the anode compartments well below the surface of the electrolyte contained therein. This gas comprises a mixture of nitrogen and chlorine, nitrogen being employed as a carrier for the chlorine and the chlorine being employed as an oxidizing agent, for a purpose more fully yexplained hereinafter. Further, the flow of mercury through the lower casing section 11 via the fourth conduit system mentioned is suitably adjusted, whereby pure mercury is introduced into the mercury pool 62 and contaminated mercury is withdrawn therefrom, as explained more fully hereinafter.

Shortly after operation of the electrolytic cell is initiated, the first and second solutions respectively displace the initial body of electrolyte 65 in the anode and cathode compartments 30 and 31, and the mixture of nitrogen and chlorine is bubbled through the first solution conducted through the anode compartments 30, whereby the oxalate solution is decomposed in order to prevent possible precipitation of minor amounts of uranous oxalate in the anode compartments. More particularly, the oxalate solution is readily decomposed by virtue of two independent, although cumulative, chemical actions which take place in the anode compartments. In the first place, the oxalate solution is decomposed into carbon dioxide by. anodic oxidation, due to contact between the oxalate ions and the anode elements 38 in the anode compartments 30, as indicated below:

In the second place, the oxalate solution is decomposed intov carbon dioxide and hydrochloric acid by chlorine oxidation, due to contact between the oxalate solution and the chlorine bubbled therethrough in the anode compartments 30, as indicated below:

It is noted that the decomposition of the oxalate solution by chlorine oxidation is enhanced by virtue of the increased temperature of the oxalate solution as a result of the treatment in thevelectrolytic cell 10. The carbon dioxide thus produced in the anode compartments 30 escapes therefrom, along with some of the chlorine and virtually all of the nitrogen originally introduced into the oxalate solution therein.

Furthermore, the hydrochloric acid thus produced in the anode compartments 30 by chlorine oxidation, as well as the hydrochloric acid conducted through the cathode compartments 31, is decomposed to a considerable extent by the electrolytic current into hydrogen and chlorine. The hydrogen ion migrates toward the Icathode members 46, where .hydrogen is liberated to some extent, and then escapes from the cathode compartments 31; while the chloride ion migrates to the anode elements 38, where chlorine is liberated freely, and then escapes from the anode compartments 30.y These gases (hydrogen, nitrogen, chlorine and carbon dioxide); escape from the anode and cathode compartments 30 and 31 in the electrolyticvcell' 10, accumulate within the interior of the ,surrounding housiug120, and are conducted therefrom by` v Ars way of the conduit 134 carried by the upper housing` amounts of nitrogen and chlorine are adequate to build up a slight pressure within the housing 120.

Also, it is noted that while it is preferable that a mix- Y ture of nitrogen and chlorine be introduced into the anode compartments 30 via the third conduit system in order to obtain rapid decomposition of the oxalate solution, this step is not essential as the oxalate solution may be decomposed quite satisfactorily entirely by anodic oxida- A Of course, it will be understood that when thel tion. oxalate solution is decomposed entirely by anodic oxidation, the rate of decomposition is correspondingly decreased. Furthermore, aside from the fact that the introduction of the mixture of nitrogen and chlorine into the anode compartments 30 is productive of decomposition of the oxalate solution by chlorine oxidation, it has been found to be desirable also from the standpoint that the.

bubbling of the gas through the first solution conducted through the anode compartments 30 produces a stirring or agitating effect, resulting in an increased contact between the oxalate solution and the anode elements 38 in the anode compartments 30 and the consequent increased rate of decomposition of the oxalate solution due to anodic oxidation, as previously explained. Further, it is pointed out that the above-mentioned stirringor agitation of the oxalate solution in the anode compartments 30 may be brought about entirely by the introduction of only nitrogen via the third conduit system. Also, instead of introducing a mixture of nitrogen and chlorine via they third conduit system, chlorine alone may be introduced into the anode compartments 30 in order to obtain the decomposition of the oxalate solution by chlorine oxidation in the manner explained. Finally in this connection, it appears that the chlorine produced as a result of the decomposition of the second solution conducted through the cathode compartments 31, which migrates to the anode elements 38 in the anode compartments 30, also accounts for some of the decomposition by chlorine oxi-r dation of the oxalate solution in the anode compartments, regardless of whether gas is introduced via the third conduit system into the anode compartments in the manner explained.

Also, as the first solution is conducted through the anode compartments 30 of the electrolytic cell, it is subjected to electrolysis as previously explained. whereby the contained ions are diffused by the electrolytic current .I

through the partition elements 28 into the second solution conducted through the cathode compartments 31. The tlow of the first solution through the anode compartments 30 of the electrolytic cell l0 is appropriately correlated with respect to the electrolytic current therei through, so that substantially all of the uranium and other metal ions are transferred by electrolytic diffusion from the first solution to the second solution, the first solution leaving the electrolytic cell 10 containing only minor traces of uranium, nickel, iron, copper and chromium in the original ionic forms: UO2++, U++++,

Ni++, Fe+++, Fe++, Cu++ and Cr+++. In view of they fact that substantially all of the uranium and other metal ions are transferred from the first solution to the second solution, a considerable concentration of the uranium in solution is effected, as the rate of flow of the second Y,

solution is only approximately one-tenth of that of the iirst solution, as previously explained.

Furthermore, substantially all of the metal ions except uranium transferred to the second solution are reduced by the electrolytic current to the metallic state; while the uranium ions transferred to the second solution are reduced by the electrolytic current lto the ionic form, U++++, in the event they are not already in this form, substantially none of the uranium ions being reduced to the metallic state, U0, due to the fact that uranium -inherently possesses a high vover-voltage. More'particularly, the Fe+++ ion is first reducedv to v the Fe++ ion and then to the metal state Feo, whilethel -Ni++, Cr+++ and Cu++ ions are respectively reduced Vto Ythe metal states Ni, Cro-and Cu, which metal impurities in thc-second solution' in., the cathode compartments 31 are carried, by therotating disks 46 into themercurypool 62.A The metalimpurities carried into the mercury .pool 62 bythe rotating disks 46 are either trapped therein or amalgamated therewith, whereby the nsecond ,solution conducted through the cathode compartments 31 is kept substantially free of metal impurities liberated therein Vincident .to the electrolysis. Speciiically, the copperrchromium. and nickel impurities readily amalgamate with the mercury in the mercury pool 62, whereas the -iron impurity is trapped therein.- In view of the fact that pure mercury is continuously conducted-through the lower casing lsection 11 of the electrolyticcell 10,the metalimpilrities introduced into the mercury pool 62-are Aconducted therefrom along withthe mercury.

Of course, it will be Yunderstood -that the mercury con,- ductedfrom the lower casingsection v11 of, thev electrolytic cell is subsequently purified and againconductedrelatively large volume of the irst solution to the rela-v tively small volume of the second solution, and to remove virtually all of the metal impurities from the tirst solution without introducing substantially any of these metal impurities into the second solution, the metal impurities being removed from the first solution by electrolysis and introduced into the mercury which is circulated through the lower casing section of the electrolytic cell.

The tlrst solution, after it is conducted from the electrolytic cell, may be discarded or subjected to further salvage treatment in order to recover any minor traces of the contained uranium; the second solution, after it is conducted from the electrolytic cell, is then subjected to further salvage treatment in order to recover the contained uranium; while the impurities recovered from the mercury circulated through the lower casing section of the electrolytic cell may be salvaged in order to recover any minor traces of uranium that may be trapped therein.

It will be understood that although the present invention is particularly useful for the separation and concentration of uranium from impure uranium oxalate solution, it also contemplates electrolytic processes wherein other solutions,.and/ or other operational conditions such as rates of flow, current densities, etc., are employed. Solutions of metal salts other than uranium salts may be passed in non-mixing ion-transfer relation with other acidic electrolytes to separate and concentrate the metals. Substantially any compound that is decomposable by chlorine oxidation may be decomposed or oxidized by electrolysis in a system comprising a solution containing chloride ion in ion transfer relation with a solution of the compound. Other known oxidizing gases than chlorine may be bubbled through the solution to assist in oxidation. Thus, it will be clear that the process of the present invention is not restricted to the illustrative details given.

In view of the foregoing, it is apparent that there has been provided an improved process of salvaging the uranium from a solution of the character and Ycomposition mentioned, derived from calutrons employed in the calutron method of producinguranium enriched with U235.

While there has been described what is at present conscope ofv the invention.

What is claimed is:

l. The process of concentrating uranium-in vsolution bytreatment in an electrolytic vcell including anode and c'athode compartments comprising passing at a relatively high rate of llow a first solution containing uranium and Oxa-- late ions through the anode compartment-of lthe electrolytic cell, passing atfa relatively low-rate of ow an acidic second solution through thecathode compartment of the electrolytic ccllin ion transfer and non-intermi'xing rela-- tion with said rstsolution, and simultaneously'subjecting'- the two solutions to electrolysis in the electrolytic cell'to transfer said uraniumions from said flrstl solution -to said second solution and concentratesaid uranium ions therein.V

2. The process of concentrating uranium in solution by `treatment in an electrolytic cell including anode and-cathi ode compartments separated by a porous diaphragm comprising passing at a relatively high rate of flow a rst solution containing uranium and oxalate ions through the anode compartment of the electrolytic cell, passing at a relatively low rate of flow an acidic second solution through the cathode compartment of the electrolytic cell, and simultaneously subjecting the two solutions to electrolysis in the electrolytic cell to transfer said uranium ions from said first solution to said second solution and to concentrate said uranium ions therein.

3. The process of concentrating uranium in solution by treatment in an electrolytic cell including anode and cathode compartments separated by a porous diaphragm comprising passing at a relatively high rate of flow an oxalate solution containing uranium ions through the anode compartment of the electrolytic cell, passing at a relatively low rate of flow a hydrochloric acid solution through the cathode compartment of the electrolytic cell, and simultaneously subjecting the two solutions to electrolysis in the electrolytic cell to transfer said uranium ions from said oxalate solution to said hydrochloric acid solution wherein said uranium ions are concentrated.

4. The process of forming a concentrated solution of uranium which comprises passing a hydrochloric acid solution of about 12 N concentration at a relatively low volume per unit time in contact with mercury and in substantially non-mixing, ion-transfer relation with an oxalate solution containing uranium in small concentration along with ions of the metals selected from the group consisting of iron, copper, nickel, and chromium and flowing at a relatively large volume per unit time, electrolyzing said solutions to cause a transfer of chloride ions from said acid solution to said oxalate solution and of the uranium and other metal ions from said oxalate solution to said hydrochloric acid solution and to effect a deposition of metal other than uranium on and in the mercury and oxidation of oxalate ions and of the chloride ions to form chlorine gas, and recycling said chlorine gas to contact said oxalate solution.

5. The process of fractionating an oxalate solution containing uranium and other metal ions including those of iron, nickel, copper, and chromium comprising introducing said solution into the anode compartment of an electrolytic cell including anode and cathode compartments arranged in ion-transfer, nonintermixing relation to each other and having a mercury cathode, introducing an acidic solution into the cathode compartment of said cell, subjecting said solution to electrolysis to transfer said uranium and metal ions from said oxalate solution to said acidic solution to reduce said iron, nickel, copper, and chromium ions to the metallic state and to deposit the same in said mercury cathode.

6. The process of forming a purified and concentrated solution of uranium comprising passing a hydrochloric 1 5 16 acid solution'in contact with mercury and in substantially References Cited in the le of this patent L nonintermixing ion transfer relation with a second acidic v UNITED STATES PATENTS solution contamlng uranium and other metal ions and 605,835 p Andreoli. June 21T-1898's K owing at a higher volumetric rate, and simultaneously l n p v applying a voltage differential between said mercury and 5 l5gg96 Bleecker 1:1 -Jan' 21, 1912*: said second solution to transfer said uranium and metal 2190 gcllgona (v' 12p ions to said second solution and to deposit said metal ions 1328955 Mtslgltn; "Feptisf in metallic form in said mercury. i f L 1 7. The process of separating uranium from other ions ghton i Y and forming a concentrated solution thereof, comprising 10 18972 17 S h as; "rig Fa; 14 1933;?. y. passing a hydrochloric acid solution of about 12 normal 1990582 y Cc Peltel'wlr 1seb. 12, 1935.., concentration in contact with mercury and in substantially 2341356 Brlg on *f -r'- Me 24 1.940: 4 nonintermixing ion transfer relation with an oxalate solu- 23 2 Griggs ay 945:1* tion of about 1 to 3 N acidity containing uranium, iron, 85 69 lobus, SePt 18 1 nickel, copper, and chromium ions and owing at a higher 15 OTHER REFERENCES volumetric rate, and simultaneously transferring said ura- Bulletin de la Societe Chimique de Paris (1901) VOL' nium and other said ions by electrolysis to said hydroume 25 pages 622 623 Anarticle by Feree i l V1 chloc acid Solution and electfolycauy depositing said Joural'ofPhysicalchemistry volume 23 (1919) pages' Y other ions from said hydrochloric acid solution into said 526, 536 543 An article by Pierh, v mefcufy- Joumn of the Chemical society (London) 1931,y pages? 2806,'2807. An article by Groves et al. i Uranium and Atomic Power by Jack De Ment etal., Chemical Pub. Co., Brooklyn, N. Y., 1941, pages 189,` 182 

1. THE PROCESS OF CONCENTRATING URANIUM IN SOLUTION BY TREATMENT IN AN ELECTROLYTIC CELL INCLUDING ANODE AND CATHODE COMPARTMENTS COMPRISING PASSING AT A RELATIVELY HIGH RATE OF FLOW A FIRST SOLUTION CONTAINING URANIUM AND OXALATE IONS THROUGH THE ANODE COMPARTMENT OF THE ELECTROLYTIC CELL, PASSING AT A RELATIVELY LOW RATE OF FLOW AN ACIDIC SECOND SOLUTION THROUGH THE CATHODE COMPARTMENT OF THE ELECTROLYTIC CELL IN ION TRANSFER AND NON-INTERMIXING RELATION WITH SAID FIRST SOLUTION, AND SIMULTANEOUSLY SUBJECTING THE TWO SOLUTIONS TO ELECTROLYSIS IN THE ELECTROLYTIC CELL TO TRANSFER SAID URANIUM IONS FROM SAID FIRST SOLUTION TO SAID SECOND SOLUTION AND CONCENTRATE SAID URANIUM IONS THEREIN. 